ObjectiveFreezing of gait is detrimental to patients with idiopathic Parkinson’s disease. Its pathophysiology represents a multilevel failure of motor processing in the cortical, subcortical, and brainstem circuits, ultimately resulting in ineffective motor output of the spinal pattern generator. Electrophysiological studies pointed to abnormalities of oscillatory activity in freezers that covered a broad frequency range including the theta, alpha, and beta bands. We explored muscular frequency domain activity with respect to freezing, and used deep brain stimulation to modulate these rhythms thereby (...) evaluating the supraspinal contributions to spinal motor neuron activity.MethodsWe analyzed 9 PD freezers and 16 healthy controls. We studied the patients after overnight withdrawal of dopaminergic medication with stimulation off, stimulation of the subthalamic nucleus or the substantia nigra pars reticulate, respectively. Patients performed a walking paradigm passing a narrow obstacle. We analyzed the frequency-domain spectra of the tibialis anterior and gastrocnemius muscles in ‘regular gait’ and during the ‘freezing’ episodes.ResultsIn stimulation off, PD freezers showed increased muscle activity of the alpha and low-beta band compared to HC in both TA and GA. This activity increase was present during straight walking and during the freezes to similar extent. STN- but not SNr-DBS decreased this activity and paralleled the clinical improvement of freezing.ConclusionWe found increased muscle activation of the alpha and lower beta band in PD freezers compared to HC, and this was attenuated with STN-DBS. Future studies may use combined recordings of local field potentials, electroencephalography, and electromyography to interrogate the supraspinal circuit mechanisms of the pathological activation pattern of the spinal pattern generator. (shrink)

Modern Jewish Philosophy and the Politics of Divine Violence Is commitment to God compatible with modern citizenship? In this book, Daniel H. Weiss provides new readings of four modern Jewish philosophers - Moses Mendelssohn, Hermann Cohen, Franz Rosenzweig, and Walter Benjamin - in light of classical rabbinic accounts of God's sovereignty, divine and human violence, and the embodied human being as the image of God. He demonstrates how classical rabbinic literature is relevant to contemporary political and philosophical debates. Weiss brings (...) to light striking political aspects of the writings of the modern Jewish philosophers, who have often been understood as non-political. In addition, he shows how the four modern thinkers are more radical and more shaped by Jewish tradition than has previously been thought. Taken as a whole, Weiss' book argues for a fundamental rethinking of the relationship between Judaism and politics, the history of Jewish thought, and the ethical and political dynamics of the broader Western philosophical tradition. (shrink)